Assembly of focal adhesions and FAK phosphorylation in RBE cells. (Ai) Representative images of serum-starved wild-type (wt) and CEACAM1-L–expressing cells plated on fibronectin (FN) or laminin-1 (LN) for 75 minutes. After removing nonadhering cells, adherent cells were fixed and stained for paxillin. Original magnification, × 400. (ii) Quantification of paxillin-containing dot-like structures per cell. □ indicates wt; ▪, CEACAM1-L–expressing cells. Means ± SD of 3 experiments are shown. ^*P < .001. (Bi) Serum-starved cells were kept in suspension (S) or attached to laminin-1 for the indicated times. Equal protein amounts were subjected to FAK immunoprecipitation, followed by immunoblotting with antiphosphotyrosine antibodies (PY99). Blots were stripped and reprobed with monoclonal anti-FAK antibodies. A representative immunoblot of 3 independent experiments is shown. (ii) Quantification of FAK-tyrosine phosphorylation during adhesion on laminin-1. ♦ indicates wt; ▪ indicates CEACAM-1–expressing cells. Fold induction represented as means ± SD from 3 independent experiments is shown. (C) Representative immunoblots showing expression levels of α6 and β1 integrins and the integrin-associated proteins talin, vinculin, FAK, and paxillin in RBE wt and CEACAM1-L–expressing cells. The results shown are representative of 2 independent experiments.